Structural Properties in Ag3SI: A Molecular Dynamics Study of Superionic and Molten Phases

Structural properties of liquid and superionic phase of Ag 3 SI are investigated by molecular dynamics simulation (MD), using the Vashishta–Rahman (VR) type potentials. The description of the pair distribution functions obtained by MD in superionic phase is in good agreement with recent neutron diffraction experiments. The features of the bond–angle distributions are obtained to confirm the structure of anions and the positions where cations prefer to reside in the lattice. The peaks of the bond–angle distributions including cations are mainly due to Ag ions at tetrahedral 12(d) sites. At molten phase, the pair distribution functions and bond–angle distributions are rather different from those in super-ionic phase, because they are distorted by thermal disturbance.